The county (or municipal) code can override the state code in some instances. Note that many county codes, however, include language that cites several other codes and notes adoption of the "most stringent" or "most protective" requirements for each circumstance. And if the county code doesn't mention an item (such as the drain pan) but adopts the state code, it is required unless specifically noted in the county code that it is not.

BOCA stands for Building Officials and Code Administrator's International. The BOCA codes and the National Standard Plumbing Code are published by independent, non-government organizations and the "level" of them relative to each other is entirely dependent on how the state or municipality chooses to adopt them.

An annotated state code simply means that a state (or municipality) can adopt a code such as NSPC or BOCA with modifications or exceptions. The modifications are collectively referred to as annotations. Remember that in general, the more "local" codes almost always override the national or general codes.

Another important term is the "authority having jurisdiction". This always refers to the most local building official (county, city or other municipality), who have the power to make exceptions or modifications to the state or national codes.

: Can county code ever override or eliminate a state code item? Is that what you mean by "...if the county adopts the state code without an exception." (Note that the hot water heater pan was just an example.) Also, is the National Standard Plumbing Code equivalent/on the same level as the BOCA National Building code? AND WHAT DOES BOCA stand for? And finally, what is meant by Annotated Code of (insert a state's name) as in: In the event of a conflict between the BOCA Code and the Annotated Code of _________, the provisions of the Annotated code of ___________ shall prevail. Thanks again for clarifying plumbing code. : : : : Your county (or other municipality) is the final arbiter of what codes to use and how to interpret them. This means that if the local guy decides that you have to paint your piping green with red stripes to satisfy a code requirement, you gotta do it.: : : Okay, but how about if the county code doesn't mention hot water heater pan required under the hot water heater but the state code does and the county plumbing inspectors don't inforce the state code. Does that mean that plumbers who install replacement hotwater heaters don't have to mention to the homeowners the need for the pans? In other words, do the county plumbers not have to comply with the state codes?.

: : If the county code references the state code (and it probably does) and does not specifically exclude the need for the pans, they are required whether the county chooses to enforce the requirement or not. Therefore, it would be incumbent on the plumber to install the heater per code, i.e. with a drain pan, if the county adopts the state code without an exception. Note that in the National Standard Plumbing Code, this pan is NOT required when the floor is a slab on grade and not subject to water damage (i.e. made of concrete).